Solve for x
x=40
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80+x-3x=0
Subtract 3x from both sides.
80-2x=0
Combine x and -3x to get -2x.
-2x=-80
Subtract 80 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-80}{-2}
Divide both sides by -2.
x=40
Divide -80 by -2 to get 40.
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